One vertex per element, one color per generator, with an edge from x to x·s.
(2,6)(7,8)(10,15)(12,22)(16,18)(19,23)(25,26,31,33)(27,34,28,30)(29,32,38,40)(35,39,36,37)(1,2,5,6)(3,7,4,8)(9,10,14,15)(11,18,21,16)(12,17,22,13)(19,20,23,24)(10,15)(12,22)(16,18)(19,23)(25,27,31,28)(26,30,33,34)(29,35,38,36)(32,37,40,39)(1,3,5,4)(2,7,6,8)(9,11)(10,16)(12,23)(13,24)(14,21)(15,18)(17,20)(19,22)(25,28,31,27)(26,30,33,34)(29,35,38,36)(32,39,40,37)(9,12)(10,17)(11,19)(13,15)(14,22)(16,24)(18,20)(21,23)(25,29)(26,32)(27,35)(28,36)(30,37)(31,38)(33,40)(34,39) involution — undirected(1,4,5,3)(2,8,6,7)(9,13,14,17)(10,12,15,22)(11,20,21,24)(16,19,18,23)(25,30)(26,27)(28,33)(29,37)(31,34)(32,35)(36,40)(38,39)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.